Method and arrangement for determining a sequence of interconnected, communication-capable modules

Abstract

The invention relates to a method for determining a sequence in which at least three interconnected, communication-capable modules (2, 2') are arranged. The method comprises the following steps: - Output of a magnetic signal from one of the modules (2, 2') with a predetermined intensity; - Increasing the intensity of the signal until the signal is detected by one of the modules (2, 2') that is directly adjacent to the sending module (2, 2'), but is not detected by one of the modules (2, 2') that is not directly adjacent; - Output of identification data by the module (2, 2') that detected the magnetic signal, via a communication channel to a detection unit; and - Determine the sequence of modules (2, 2') based on the identification data. The invention further relates to an arrangement (1) of at least three interconnectable communication-capable modules (2, 2'), each having a coil (9) for outputting and / or receiving a magnetic signal, and a detection unit, wherein the arrangement (1) is configured to carry out a method.

Description

[0001] The invention relates to a method for determining a sequence in which at least three communication-capable modules are arranged in a row. The invention further relates to an arrangement of at least three communication-capable modules arranged in a row, with which such a method can be carried out.

[0002] In electrical installation and automation technology, arrangements of communication-capable modules arranged in series are often used. One example from automation technology are so-called "remote I / O" systems, i.e., systems for the input and output of signals and / or data that are located remotely from a control device, e.g., in a control cabinet. These systems typically comprise a head module, also called a head station, which establishes a connection to the control system, and several I / O (input / output) modules that are attached to the head module. For this purpose, the modules each have a DIN rail mount and usually also locking devices for mechanical connection to an adjacent module.

[0003] Mechanical arranging can also be used to establish electrical connections between modules, for example, to establish a power supply bus and / or a data bus between the modules and the head station. Even if it is not absolutely necessary for the functionality of the bus system, it may be of interest for additional services to obtain information about the sequence in which the modules are arranged. For example, this information can simplify troubleshooting on the I / O system, since the physical position of a faulty module can be visualized if the sequence is known.

[0004] The same problem can also arise with modules arranged in series that do not establish a wired data bus when connected, but rather communicate independently wirelessly with a distribution system, such as a switch or gateway. In this case, too, the sequence of these independently communicating modules may be of interest.

[0005] It is an object of the present invention to describe a method with which a sequence of sequentially arranged communication-capable modules within an array can be determined. A further object is to describe an arrangement of sequentially arranged communication-capable modules suitable for implementing the method.

[0006] This problem is solved by a method or arrangement having the features of the respective independent claim. Advantageous embodiments and further developments are the subject of the dependent claims.

[0007] A method according to the invention of the type mentioned above is characterized by the following steps: A magnetic signal is transmitted from a first of the modules with a predetermined intensity. The intensity of the signal is then increased, for example, continuously or gradually, until the signal is detected by a module directly adjacent to the transmitting module, but not by a module not directly adjacent to it. After detecting the signal, the module that detected the signal transmits its identification data via a communication channel to a detection unit, which uses the identification data to detect a sequence of the modules.

[0008] According to the invention, a magnetic signal is emitted by the first module, independent of the communication channel, and its intensity is increased. Increasing the intensity increases the range within which the magnetic signal can be detected by another module with a given detection sensitivity. The increase in the signal intensity ensures that the signal is first detected by an immediately adjacent module. This module then identifies itself as an immediate neighbor using its identification data, which is transmitted over the communication channel.

[0009] The process thus exploits the increasing range of the magnetic signal to detect a module and then uses the communication channel to transmit the identification data. Furthermore, the communication channel can also be used to coordinate the process among the various participating units, i.e., the modules and the detection unit.

[0010] The sequence determination is independent of the type of communication channel and can be used for both wired and wireless modules. Communication can also take place via a bus system or a network.

[0011] An arrangement according to the invention comprises at least three modules, each having a communication unit, as well as a coil for emitting and / or receiving a magnetic signal. The arrangement further comprises a detection unit and is configured to carry out the aforementioned method.

[0012] Preferably, a module with this distinction is used as the first module, located at an outer edge of the array. This eliminates any potential ambivalence that might arise from the possibility of a nearest neighbor on each side. Arrays of the type described often have a module at an outer edge that also functions as a bus master for a data bus established among the modules. Such a module, which represents the bus master in the array, is a preferred choice for the first module of the method according to the invention.

[0013] In an advantageous development of the method, after the receiving module's identification data has been output, the signal intensity is further increased until the magnetic signal is detected by another module. This additional module also outputs its identification data. Based on the identification data, a list of the arranged modules can be continued, for example. This process can be repeated in the same way until all modules in the array have been detected.

[0014] In a further advantageous embodiment of the method, after the signal has been detected, the output of the signal from the first module is terminated and a further magnetic identification signal is output from the module that has output its identification data. In this way, the method can also be carried out with an arrangement comprising a large number of modules, even if the magnetic identification signal, originating from a first module at the edge of the arrangement, does not extend to the last module at the opposite edge of the arrangement. Preferably, said first module then no longer participates in the method and, in particular, no longer reacts to magnetic fields that are still transmitted within the scope of this identification cycle.

[0015] In one embodiment, a coil is arranged in each module to output and / or receive the magnetic signal, with an axial direction of the coil aligned in the direction in which the modules are arranged. Preferably, the coils are positioned within the modules such that all coils are arranged on a common axis when the modules are arranged in series. Preferably, the coils are arranged on a coil core, which also extends in the direction in which the modules are arranged. Particularly preferably, the core is a rod-shaped core open on both sides, in particular a ferrite core.

[0016] More preferably, the magnetic identification signal is generated by applying an electrical pulse of variable length to the coil. In particular, the pulse is a rectangular voltage pulse. Due to the coil's inductance, the magnetic field strength increases monotonically, in a first approximation linearly, over time when a rectangular voltage pulse is applied to the coil, so that the signal is generated with a magnetic field strength amplitude that depends on the length of the voltage pulse. Thus, the range of the magnetic signal can be easily varied by varying the pulse length.

[0017] The invention is explained in more detail below using exemplary embodiments and figures. The figures show: Fig. 1 an arrangement of several communication-capable modules arranged in a row in a spatial representation; Fig. 2 a side view of the arrangement according to Fig. 1; Fig. 3 a partially sectioned spatial representation of a head module of the arrangement of the Fig. 1 and Fig. 2; Fig. 4 a spatial representation of another module of the arrangement of the Fig. 1 and Fig. 2; and Fig. 5 a flowchart of an embodiment of a method for determining a sequence of modules arranged in series.

[0018] Fig. 1 initially shows, in a spatial representation, an arrangement 1 of communication-capable modules 2, 2' arranged in a row. The modules 2, 2' of the arrangement 1 form, by way of example, a so-called "remote I / O" system, i.e., an input or output station for analog and / or digital signals that is connected to a control system and can be positioned remotely from it. Fig. 2 shows the arrangement 1 according to Fig. 1 in a side view.

[0019] In the arrangement 1 shown, module 2 represents a so-called head module (head station) and is also referred to below as head module 2. The other modules 2' are input and output modules and are also referred to below as I / O modules 2' for simplicity.

[0020] All modules 2, 2' each have a housing 3, which is shown here in the Fig. 1 is equipped in the lower area with a mounting rail holder 4 for snapping onto a mounting rail, for example in a control cabinet. Fig. 1 The side shown below is facing away from the user when assembly 1 is installed, while the side shown in the Fig. 1 The side shown above usually represents a front side of arrangement 1 and is facing the user in the control cabinet.

[0021] The head module 2 includes connectors 5, which are used to connect a fieldbus, which the head module 2 uses to communicate with a control device (not shown here). A CAN bus or an Ethernet-based fieldbus, such as an EtherCAT bus, can be used as a fieldbus connection.

[0022] The connectors 5 are permanently installed in the housing 3. In addition, the head-end station 2 has further connectors 6, e.g., for the power supply, which are designed as interchangeable connector blocks that can be inserted into a corresponding recess on the top of the housing 3.

[0023] The I / O modules 2' are also placed on the mounting rail and are snapped onto the head module 2 or onto an adjacent I / O module 2', whereby the Fig. The arrangement 1 shown in Figure 1 is created modularly. The number of four I / O modules 2' here is purely exemplary. The I / O modules 2' also have interchangeable connectors 6 on their front side when installed in the control cabinet. These connectors are used to connect sensors and / or actuators, for example, in an industrial plant or building automation system.

[0024] When the modules 2, 2' are arranged in series, a power supply bus and a data bus are formed by contacts (not visible here) on the mutually facing side surfaces of the modules 2, 2', which connect the head module 2 and the I / O modules 2' to each other with regard to a power supply and data exchange.

[0025] The internal structure of the head module 2 is also shown again in a partially sectioned drawing in Fig. 3 and the internal structure of one of the I / O modules 2' in a representation in Fig. 4, in which one side part of the housing has been removed. In these illustrations, it can be seen that both the head module 2 and the I / O modules 2' each have at least one printed circuit board 7, which is aligned perpendicularly to the mounting rail within the housing 3. The head module 2 has further printed circuit boards 8, some of which are arranged in a different orientation than the printed circuit board 7 in the housing 3. In the I / O module 2', in the illustration of the Fig. 4 also data bus contacts 10 can be seen.

[0026] A coil 9 is arranged at a comparable position on the circuit board 7 for each of the modules 2, 2'. For example, the coil 9 is designed as a bar coil on a core open on both sides. The core can be a ferrite core, for example. When the modules 2, 2' are lined up to form the arrangement 1, the longitudinal axes of all coils 9 are essentially on an axis that runs parallel to the mounting rail. For simplicity, the circuit boards 7, 8 are shown without any additional electrical or electronic components.

[0027] The coils 9 serve, as shown below in a flow diagram in Fig. 5, according to the application, to detect a respective next, adjacent module 2' starting from the head module 2 and thereby to determine an order of the arrangement of the modules 2, 2' with the aid of a detection unit.

[0028] The Fig. The embodiment of a method according to the application for determining the sequence of the modules 2, 2' arranged in series, shown in Figure 5, is described by way of example with reference to the arrangement 1 of Fig. 1 and Fig. 2. However, it is understood that the method can also be carried out with other arrangements of modules 2, 2' arranged in series. In particular, it is not necessary for the implementation of the method that the modules 2, 2' are connected to each other via a wired data bus, as is the case in the example of Fig. 1 and Fig. 2 is the case. The method can also be implemented with modules that are independently part of a wireless communication network. The term "communication channel" used in the following explanation is not to be understood as restrictive in this sense and can be formed via a data bus or a communication network.

[0029] For the following procedure, it is assumed that the acquisition unit, which coordinates the described procedure and acquires the sequence of the modules 2, 2', is located in the head module 2. This is also not necessary: ​​the procedure could also be coordinated by an acquisition unit located outside the head station 2, as long as the head station 2 and the I / O modules 2' can communicate with this acquisition unit.

[0030] A first step S1 in the flowchart of the Fig. 5 is an optional step in which a subsequent detection process is announced to the I / O modules 2' or, if applicable, also to the head module 2. Following this announcement, the modules 2, 2' activate a detection circuit for a signal induced in the respective coil 9. If step S1 is not provided, the corresponding detection circuits are permanently active.

[0031] In a following step S2, a counting variable n for a module number is set to an initial value, for example to the value zero: n=0.

[0032] In a following step S3, a variable T for a pulse length is also set to an initial value, for example the value Tmin: T=Tmin.

[0033] In a subsequent step S4, a voltage pulse of pulse length T is then applied to coil 9 from a first of the modules 2, 2', to which the module number of the initial value is assigned, resulting in the output of a magnetic signal of a specific amplitude. For example, it is assumed that the module with the initial number (n=0) is head module 2.

[0034] When coil 9 is subjected to a substantially rectangular voltage pulse, the current in coil 9 increases linearly within the pulse length T, to a first approximation, with the magnetic field strength of the generated magnetic field also increasing linearly. The longer the pulse lasts, the greater the field strength of the magnetic field generated by coil 9 becomes.

[0035] In a subsequent step S5, it is determined whether one of the I / O modules 2' has detected the magnetic pulse emitted by the coil 9 of the head module 2. For this purpose, the I / O modules 2' monitor a voltage induced in their coil 9. If the induced voltage exceeds a threshold value, the corresponding module 2' sends a message via a communication channel to the detection unit that a magnetic field has been detected. The communication channel is in the arrangement 1 of the Fig. 1 and Fig. 2 the data bus established between the head module 2 and the I / O modules 2'.

[0036] If a response from one of the I / O modules 2' is received within a predetermined time period, for example, in the range of one to several milliseconds, the method branches to a next step S6. If no message is received within the predetermined time period, the method continues to a step S8.

[0037] In step S6, identification data of this module 2', for example its bus address, sent along with the message of the I / O module 2', are entered in the detection unit into a list in which the order of the modules 2, 2' is subsequently reflected.

[0038] Furthermore, it can be provided that configuration data is sent from the acquisition unit to the I / O module 2' that sent the message, for example, a module number to be assigned to it. Advantageously, the value (n+1) is assigned as the module number.

[0039] In a subsequent step S7, the counting variable n is then incremented by the value 1 and the method branches back to step S3, in which the pulse width T is set back to the initial value Tmin.

[0040] The method then repeats step S4, in which a magnetic pulse is emitted. However, this time the magnetic pulse is no longer emitted by the head-end station 2, but rather by the very I / O module 2' that previously detected the magnetic field. This can be done based on a corresponding command that the detection unit sends to the I / O module 2' via the communication channel.

[0041] In the subsequent step S5, which is repeated again, the system waits for a response from one of the not yet detected I / O modules 2'. An already detected I / O module 2', and in particular the I / O module 2' currently transmitting the magnetic pulse, has deactivated its detection circuit.

[0042] If in step S5 no further I / O module 2' reports via the communication bus within the predetermined time period that it has detected a magnetic signal, the method continues in step S8, in which the variable T for the pulse width is increased by a predetermined value ΔT.

[0043] In the next step S9, a check is made to determine whether a predefined maximum pulse length Tmax has been reached. If the maximum pulse length Tmax is reached, the method is terminated. If the maximum pulse length Tmax is not reached, the method branches back to step S4, in which a magnetic pulse is again output by the same I / O module 2' as before, but this time with the pulse length T extended by the value ΔT and thus with a larger magnetic field amplitude.

[0044] Steps S4 to S9 are repeated, if necessary, until either one of the previously undetected I / O modules 2' detects the magnetic signal or until the maximum pulse length Tmax is reached. By gradually increasing the magnetic field amplitude, the range of the magnetic pulse (at a given detection sensitivity) is increased. In this way, the closest adjacent I / O module 2 is detected as the next module 2, 2'. In this method, all of the connected I / O modules 2' are successively detected in the order of their arrangement, starting from one side of the arrangement 1—here specifically starting from the head module 2. Reference symbol 1 arrangement 2 Module (head module) 2' additional module (I / O module) 3 housings 4 mounting rail holder 5 Connection (fixed) 6 connector (replaceable) 7 Circuit board 8 additional circuit boards 9 coil 10 data bus contacts

Claims

[1] Method for determining a sequence in which at least three communication-capable modules (2, 2') are arranged in a row, comprising the following steps: - outputting a magnetic signal from a first of the modules (2, 2') with a predetermined intensity; - increasing the intensity of the signal until the signal is detected by one of the modules (2, 2') immediately adjacent to the transmitting module (2, 2'), but is not detected by one of the modules (2, 2') not immediately adjacent; - outputting identification data by the module (2, 2') that has detected the magnetic signal to a detection unit via a communication channel; and - Determine a sequence of the modules (2, 2') based on the identification data. [2] Method according to claim 1, wherein, after the identification data has been output by the module (2, 2') which has detected the magnetic signal, the intensity of the magnetic signal sent by the first of the modules (2, 2') is further increased until the magnetic signal is detected by another of the modules (2, 2'), which then transmits identification data to the detection unit via the communication channel. [3] Method according to claim 1, wherein, after outputting the identification data, the module (2, 2') which has detected the magnetic signal outputs the magnetic signal increasing from the predetermined intensity until the magnetic signal is detected by another module (2, 2'), which then transmits identification data to the detection unit via the communication channel. [4] Method according to claim 2 or 3, wherein the steps of outputting the magnetic signal, detecting the magnetic signal by another of the modules (2, 2') and transmitting the identification data are carried out repeatedly until all modules (2, 2') of the arrangement (1) are detected. [5] Method according to one of claims 1 to 4, wherein the detection unit, after receiving the identification data, transmits configuration data to the module (2, 2') that sent the identification data. [6] Method according to one of claims 1 to 5, wherein the magnetic signal is generated and / or detected by a respective coil (9) arranged in each of the modules (2, 2'). [7] Method according to claim 6, wherein the magnetic signal is a magnetic pulse which is generated by applying a rectangular voltage signal of a predeterminable pulse width (T) to the coil (9). [8] Method according to claim 7, wherein the intensity of the magnetic signal is increased by increasing the pulse width (T). [9] Arrangement (1) comprising at least three communication-capable modules (2, 2') which can be arranged in series and each have a coil (9) for outputting and / or receiving a magnetic signal, as well as a detection unit, wherein the arrangement (1) is designed to carry out a method according to one of claims 1 to 8. [10] Arrangement (1) according to claim 9, wherein all coils (9) are arranged along a common axis. [11] Arrangement (1) according to claim 9 or 10, wherein the coils (9) are bar coils. [12] Arrangement (1) according to one of claims 9 to 11, wherein the coils (9) have a ferrite core.

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